1. Field of the Invention
The present invention relates to a cassette for receiving a plurality of glass substrates, and more particularly, to a cassette for facilitating an etching of a plurality of glass substrates, wherein the cassette includes a stopper for preventing glass substrates from exiting a rear portion of the cassette.
2. Discussion of the Related Art
Flat panel display devices such as Liquid Crystal Displays (LCDs), Plasma Display Panels (PDPs), Electro-Luminescence Displays (ELD), and Vacuum-Fluorescent Displays (VFD) have recently been the subject of intense research and development. Of the aforementioned flat panel display devices, particular attention has been directed toward LCDs due to their ability to express images at a high resolution while consuming low amounts of power.
Despite the widespread applications of LCD devices as monitors of portable televisions and notebook computers, problems that need to be resolved still exist. For example, the weight and/or size of LCD devices must decrease to enable users to carry the LCD devices used in portable televisions or notebook computers. Even though various methods for decreasing the weight and/or size of LCD devices exist, it is desirable, though difficult, to decrease weight or size of essential elements within the LCD device using present techniques. For example, it is desirable to decrease the weight of glass substrates, the heaviest of the essential elements within the LCD device.
To decrease their weight, glass substrates are dipped into a container filled with an etchant and surfaces of the glass substrate are etched. However, according to the aforementioned etching process, the surface of a glass substrate may be unevenly etched when, for example, particles generated during the etching process are deposited on the surface of the glass substrate. Accordingly, the generated particles may form a sludge on an edge surface of the glass substrate.
LCD devices generally include LCD panels which typically include two glass substrates bonded together, wherein one glass substrate supports a color filter and the other supports a thin film transistor (TFT). By decreasing the weight of the glass substrates within the LCD panel, the overall weight of the LCD panel may be reduced. Accordingly, to reduce the weight of LCD panels, a glass substrate is etched at an etching station and, after being etched, is loaded to a cleaning station where particles deposited on the surface of the etched glass substrate are removed with distilled water. Next, the cleaned glass substrate is loaded into a drying station.
The etching station includes a container filled with an etchant such as a hydrofluoric acid (HF) solution. A cassette holding a plurality of glass substrates is dipped into the etchant within the etching station and, after the plurality of glass substrates in the cassette are etched, is loaded to a cleaning station where particles deposited on the surface of the etched glass substrates are removed with deionized (DI) water. At the cleaning station, the cassette moves upward and downward to allow the deionized water (DI) to be sprayed uniformly onto the plurality of glass substrates. Accordingly, the uniformly sprayed deionized (DI) water removes any HF solution remaining on the surfaces of the glass substrates and sludge formed at edges of the glass substrates. After the aforementioned cleaning process is performed twice, the cassette is loaded into the drying station. Accordingly, using the aforementioned cassette, a plurality of glass substrates, provided in a multi-layered arrangement, are etched simultaneously.
FIG. 1 illustrates a perspective view of a related art cassette used in etching a plurality of glass substrates. FIG. 2 illustrates a perspective view of the related art cassette shown in FIG. 1 having an altered orientation during an etching process.
Referring to FIGS. 1 and 2, a plurality of glass substrates 1 are received by the cassette 2 and are provided within the cassette 2 in a multi-layered arrangement. Two bar-shaped two stoppers 25 are formed at the rear of the cassette 2. The stoppers 25 prevent the plurality of glass substrates 1 from exiting a rear portion of the cassette 2 when the plurality of glass substrates 1 are loaded along substantially a horizontal direction into the cassette 2, oriented substantially vertically (as shown in FIG. 1). The stoppers 25 further prevent the plurality of glass substrates 1 from exiting a rear portion of the cassette 2 when the cassette 2 is oriented substantially horizontally (as shown in FIG. 2).
The related art cassette 2 and stoppers 25 are formed of PVC, a material resistant to etchant. Forming the related art cassette 2 and stopper 25 of PVC, however, is disadvantageous because PVC has a hard surface and may crack or scratch the glass substrates 1. Side portions of the glass substrates 1 are susceptible to breaking upon exposure to external impacts. When the cassette 2 is oriented between its horizontal and vertical positions, the glass substrates 1 may collide with the stoppers 25. Accordingly, the side portions of the glass substrate 1 that collide with the stoppers 25 may break or crack. Further, glass substrates 1 containing cracks may subsequently be broken as a result of being pressed.